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Nereid
2010-Mar-12, 01:50 AM
Confirmation of general relativity on large scales from weak lensing and galaxy velocities (http://arxiv.org/abs/1003.2185)

And is this a heavy-weight paper? To answer that with a question; among contemporary astronomers, who has unquestionably greater heft that Gunn?

01101001
2010-Mar-12, 05:13 AM
Popular consumption, Science Daily: Galaxy Study Validates General Relativity on Cosmic Scale, Existence of Dark Matter (http://www.sciencedaily.com/releases/2010/03/100310134152.htm)


An analysis of more than 70,000 galaxies by University of California, Berkeley, University of Zurich and Princeton University physicists demonstrates that the universe -- at least up to a distance of 3.5 billion light years from Earth -- plays by the rules set out 95 years ago by Albert Einstein in his General Theory of Relativity.

By calculating the clustering of these galaxies, which stretch nearly one-third of the way to the edge of the universe, and analyzing their velocities and distortion from intervening material, the researchers have shown that Einstein's theory explains the nearby universe better than alternative theories of gravity.


One major implication of the new study is that the existence of dark matter is the most likely explanation for the observation that galaxies and galaxy clusters move as if under the influence of some unseen mass, in addition to the stars astronomers observe.
[...]
Seljak noted that these tests do not tell astronomers the actual identity of dark matter or dark energy. That can only be determined by other types of observations, such as direct detection experiments.

Jerry
2010-Mar-12, 07:36 PM
http://arxiv.org/abs/1003.2213

Large-scale coherent orientations of quasar polarisation vectors: interpretation in terms of axion-like particles


We have reviewed the observations of large-scale alignments of quasar polarisation vectors. The contribution of interstellar polarisation has been shown to be negligible and the existence of preferred directions, depending on the redshift, has been proved to be robust.

The current status of an explanation in terms of the mixing of the incoming photons with nearly massless axion-like particles in external magnetic fields has then been discussed; the main missing ingredient being the size and the configuration of the magnetic fields on the line of sight needed to reproduce the whole set of observations.

Where there is smoke there is fire: Where there is polarization there is an electromagnetic field: Where there is an electromagnetic field there is ionized mass: Where there is ionized mass there is radiation transfer: Where there is radiation transfer there is 1) lensing and 2) frequency shift. This is as fundamental as hetrodyning in a vacuum tube.

Sometimes the simplest explanation is the best.

tusenfem
2010-Mar-15, 05:42 AM
Where there is smoke there is fire: Where there is polarization there is an electromagnetic field: Where there is an electromagnetic field there is ionized mass: Where there is ionized mass there is radiation transfer: Where there is radiation transfer there is 1) lensing and 2) frequency shift. This is as fundamental as hetrodyning in a vacuum tube.

Sometimes the simplest explanation is the best.

Simple is okay, but first you would have to get the list correct. You seem to draw conclusions that have absolutely no basis, apart from the fact that you use all kinds of physical terms wrongly.